Relief efforts at the site of last week's volcanic eruption in eastern Congo are now getting into full swing following some setbacks in the emergency program on its first day.

For nearly a week after Mount Nyiragongo erupted, relief efforts for victims were concentrated in the Rwandan town of Gisenyi.

Aid agencies were too concerned about safety to distribute food across the border in Goma itself until Wednesday. The town was literally split in half by a lava flow, and aid workers feared the volcano could erupt again.

But most of the refugees refused to stay in Rwanda and instead came back home to Goma - even if they had no houses to come back to. Many are staying with friends or relatives.

And after a rocky start aid agencies are now distributing food to the refugees on the Congolese side of the border.

Workers have unloaded trucks full of cornmeal and cooking oil, as thousands of people lined up at sites around Goma to pick up their weekly rations.

Each family that has registered for aid has been issued an identity card. Workers checked those cards against a master list before allowing people to collect their food.

The process has hit a few snags, though. For at least one distribution site, no aid was handed out until Thursday.

David Snyder of Catholic Relief Services says they had to wait a day because authorities stopped one of their food trucks at the Rwandan border.

"There have been some difficulties in the last 24 hours with trying to come across the border into Goma here from Rwanda. And that could potentially become even a bit more problematic. But in the meantime we'll just keep going as we can," he said.

He says the crowd took the news very well, and everyone came back Thursday to get their food. Once it started, the distribution appeared to be going smoothly.

At another distribution site, aid workers say they had no problem getting food delivered. But they did have trouble with crowd control while they were trying to hand it out.

Francois Xavier of the aid agency Save the Children said things did not go as smoothly on day one, when unregistered people showed up demanding food.

He says, in fact there was a problem Wednesday. There were intruders, and they forced us to stop the distribution process.

He stands in front of sacks of cornmeal and cooking oil left over from the day before. The first thing on the agenda was distributing that food to the people who should have gotten it then. Then they had to begin handing out Thursday's rations.

Meanwhile, a group of United Nations-sponsored scientists are in Goma studying the volcano and trying to decide whether the danger is really over.

The scientists are volcano specialists known as vulcanologists. They say Mount Nyiragongo has stopped erupting for now, but they are worried about the frequent earthquakes that continue to shake the area.

They admit they are stumped as to what is causing them. But it does not fit in with the usual pattern of tremors before an eruption, not after it. They cannot say whether the earthquakes are a warning that the volcano is about to blow its top again, or simply an unusual after-effect.

The scientists believe damage to the volcano itself caused by last week's eruption means the next one - whether it is tomorrow or 20 years from now -is likely to pose an even greater danger to residents of Goma. They say the lava flow is likely to start closer to town, which will give people less time to get away.